The students of the 121 Express bus are infamous for their bad behaviour and Lucas Samson knows his role on the bus will determine his social standing at his new school. Lucas is tired of being one of the nerds. When he attracts the negative attention of the cool troublemakers, he saves himself by teasing another kid. His ploy works and soon Lucas is right in the centre of the mayhem on the bus. He loves his newfound popularity, but when the fun and games push the bus driver to a nervous collapse and hospitalizes an elderly lady, Lucas begins to question his choices.